It is believed that the subject matter of the present invention is classifiable in class 426/248 and/or class 21/102.
For relevant prior art, see U.S. Pat. No. 3,589,862. As pointed out in that patent, it is highly undesirable to permit direct contact from the liquid being treated and the window transparent to radiation due to the fact that such direct contact results in mineral deposits on the window which interferes with proper transmission of the radiation to the liquid. The solution disclosed in said patent includes an inflatable bag to confine the liquid. However, such inflatable bag does not solve the problem since the bag over a period of time will have mineral deposits accumulated on its inner surface and will therefore also be subjected to the problem sought to be overcome, namely the prevention of deposited minerals which interfere with transmission of ultraviolet rays to the liquid being treated.
The present invention utilizes an air pocket as the sole means for preventing direct contact between the liquid and the window transparent to radiation, with air being introduced into the liquid to maintain the pocket and thereby prevent the accumulation of mineral deposits on any surface which would interfere with the transmission of ultraviolet rays.